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71.
8,12-Dibromo-5,15-bis(pentafluorophenyl)corrole and its Ag(III) complex were prepared via intramolecular oxidative coupling of a 8,12-dibromobilane precursor. The Ag(III) complex was allowed for further transformation via Suzuki coupling reaction. Thus, 2-aminophenyl group was coupled at one of the β-positions, and subsequent demetalation followed by oxidation with MnO2 afforded 8,10-fused iminoisocorrole in good yields. The iminoisocorrole exhibited weak antiaromaticity due to the C(+)−N(−) polarized resonance contribution as evidenced by 1H NMR spectrum, UV/vis absorption spectra, cyclic voltammetry, and theoretical calculations.  相似文献   
72.
We developed a one‐pot reaction combining an exchange reaction of the benzylidene moiety in an acyl hydrazone with styrene radical polymerization. The one‐pot reaction of a styrene derivative bearing a 4‐(dimethylamino)benzylidene acyl hydrazone moiety was conducted in the presence of 4‐cyanobenzaldehyde and pyridinium p‐toluene sulfonate/H2O for the exchange reaction and AIBN as the radical polymerization initiator in N,N‐dimethylformamide at 70 °C for 20 h. The exchange reaction proceeded quantitatively, with the 4‐(dimethylamino)benzylidene acyl hydrazone moiety being exchanged with 4‐(methoxy)benzylidene acyl hydrazone, and polymerization proceeded smoothly to provide the corresponding polymer in 70% yield. Compared to traditional stepwise methods and polymer post‐polymerization modifications, this one‐pot system exhibits distinct advantages for the facile and efficient preparation of various functional polymers. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 2505–2510  相似文献   
73.
Feroniellin analogs isolated from Feroniella lucida possess a furanocoumarin skeleton connected to monoterpenic five- to seven-membered ethereal rings by an ether linkage and exhibit a broad spectrum of biological activities. In this contribution, we intended to establish a “ring-size-divergent” synthetic strategy for the monoterpenic five- to seven-membered ethereal rings through the chemical sythesis of feroniellins. The short and comprehensive synthesis of feroniellins was achieved in only two steps from easily available bergamottin based on the “ring-size-divergent” strategy. In addition, these syntheses resulted in revision of the proposed structures for feroniellins A and B and the determination of all the absolute configurations of feroniellins; their preliminary anti-inflammatory activities were investigated as well.  相似文献   
74.
Transparent fused silica (SiO2) microspheres 2.5 μm in diameter were photochemically welded to transparent, flexible silicone rubber ([SiO(CH3)2]n) substrate by 193 nm ArF excimer laser induced photochemical modification of silicone into silicon oxide. Single layer of silica microspheres was easily formed on an adhesive silicone rubber before laser irradiation after dropping of silica microspheres dispersed in ethanol and subsequent tape peeling. The welding rate, the percentage of welded microspheres tested by ultrasonic cleaning with ethanol, was examined by varying the single pulse fluence and irradiation time of ArF excimer laser. The welding layer underneath microsphere, silicon oxide, was also found to emit white light of strong intensity under UV light illumination.  相似文献   
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76.
The construction of well-defined transition-metal clusters has attracted substantial attention due to their unique chemical and/or physical properties. Metal clusters with 1D or 2D structures are now accessible by template-synthesis methods, in which multiple metal atoms are arranged with the aid of template molecules and their 1D or 2D structures. However, the rational synthesis of 3D clusters remains challenging, mostly due to a lack of appropriate template molecules. Herein, we report the rational synthesis of a 2D butterfly shaped Pd4 framework ( 2 ) and 3D edge-sharing Pd6 tetrahedra ( 5 ) by treatment of easily available organosilicon compounds with Pd(CNtBu)2. The diphenylsilylene moiety thereby serves as the key component to generate the butterfly structure of the Pd4 clusters in 2 . A dimensionality expansion, induced by two Cl atoms, of two butterfly shaped Pd4 subunits supported by two diphenylsilylene moieties afforded the edge-sharing tetrahedral architecture of the Pd6 cluster in 5 .  相似文献   
77.
Journal of High Energy Physics - The Goldstone equivalence theorem allows one to relate scattering amplitudes of massive gauge fields to those of scalar fields in the limit of large scattering...  相似文献   
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79.
An optically active, π-stacked poly[2,7-bis(4-tert-butylphenyl)dibenzofulvene] having a preferred-handed helical conformation was synthesized by anionic polymerization. A thin film sample of the polymer exhibited broad-band white circularly polarized light (CPL) emission on photo excitation.  相似文献   
80.
Electrochemical reactions of sulfur supported on three-dimensionally ordered macroporous carbon in glyme-Li salt molten complex electrolytes exhibit good reversibility and large capacity based on the mass of sulfur, which suggests that glyme-Li salt molten complexes are suitable electrolytes for Li-S batteries.  相似文献   
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